Tunable electrocatalytic nitrogen reduction reactions via polarization switching on In₂Se₃-based single-atom...

The tunability of two-dimensional (2D) ferroelectric-based single-atom catalysts shows great potential in electrocatalytic nitrogen reduction reactions (NRRs). This work systematically investigates the influence of polarization switching on the NRR performance of transition metal (TM) adsorbed α-In₂Se₃ monolayers using first-principles calculations. Obviously, polarization switching in the α-In₂Se₃ monolayer can cause the redistribution of electrons between TM atoms and intermediates, thereby altering the adsorption strength and energy barrier. After the screening of stability, catalytic activity, and selectivity, Re@P↑-In₂Se₃ and Mo@P↑-In₂Se₃ systems exhibit outstanding catalytic activity with a limiting potential U_L of -0.39 V, surpassing that (-0.50 V) of the excellent NRR electrocatalyst Re (111). In addition, correlations between the U_L and three descriptors E_*NNH, E_*NH2, and M_t (total magnetic moment) are established to explore the trend of changes in NRR activity. The catalytic activity of TM@P↑-In₂Se₃ and TM@P↓-In₂Se₃ can be enhanced by appropriately increasing E_*NH2 and decreasing E_*NNH. Moreover, TM@In₂Se₃ systems with larger M_t exhibit superior catalytic activity. These ferroelectric controllable TM@In₂Se₃ monolayers can be used for designing efficient nitrogen fixation electrocatalysts.